From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756675Ab0EZPd2 (ORCPT ); Wed, 26 May 2010 11:33:28 -0400 Received: from mx1.redhat.com ([209.132.183.28]:14946 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756676Ab0EZPdY (ORCPT ); Wed, 26 May 2010 11:33:24 -0400 From: Jeff Moyer To: KOSAKI Motohiro Cc: linux-kernel@vger.kernel.org, linux-ext4@vger.kernel.org, jens.axboe@oracle.com, vgoyal@redhat.com Subject: Re: [PATCH 0/4 v4] ext3/4: enhance fsync performance when using CFQ References: <1274206820-17071-1-git-send-email-jmoyer@redhat.com> <20100519105706.8821.A69D9226@jp.fujitsu.com> X-PGP-KeyID: 1F78E1B4 X-PGP-CertKey: F6FE 280D 8293 F72C 65FD 5A58 1FF8 A7CA 1F78 E1B4 X-PCLoadLetter: What the f**k does that mean? Date: Wed, 26 May 2010 11:33:17 -0400 In-Reply-To: <20100519105706.8821.A69D9226@jp.fujitsu.com> (KOSAKI Motohiro's message of "Wed, 19 May 2010 11:05:20 +0900 (JST)") Message-ID: User-Agent: Gnus/5.110011 (No Gnus v0.11) Emacs/23.1 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org KOSAKI Motohiro writes: > Hi Jeff, > >> This patch series addresses a performance problem experienced when running >> io_zone with small file sizes (from 4KB up to 8MB) and including fsync in >> the timings. A good example of this would be the following command line: >> iozone -s 64 -e -f /mnt/test/iozone.0 -i 0 >> As the file sizes get larger, the performance improves. By the time the >> file size is 16MB, there is no difference in performance between runs >> using CFQ and runs using deadline. The storage in my testing was a NetApp >> array connected via a single fibre channel link. When testing against a >> single SATA disk, the performance difference is not apparent. > > offtopic: > > Can this patch help to reduce a pain of following much small files issue? > > http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=578635 Perhaps. I don't have a debian system handy to test that, though. Cheers, Jeff